Actuating devices are known in the form of switches, in which frequently a piezoelectric element is used as a pressure-sensitive element of the sensor.
The sensitive region of such a sensor, i.e. the region to which a user normally has to apply finger pressure in order for the control system to initiate actuation of the sanitary appliance, is in most cases of relatively small spatial extent. It is usually provided with an elastic cover, which corresponds substantially to the size of the sensitive region of the sensor. A user of the sanitary appliance must take care to apply finger contact as precisely as possible to this sensitive region.
This is because, if the user does not contact the sensitive region of the sensor with sufficient precision, but presses on a location away from the sensitive region of the sensor, it might be the case that, since the pressure is not acting on the sensitive region of the sensor and the latter is not responding, from the user's perspective the switch was actuated but there is no corresponding operation of the sanitary appliance. Moreover, comparatively large amounts of force are required to operate such a sensor. Overall, therefore, the user of the sanitary appliance might be inconvenienced.
In addition, owing to the predetermined geometry of the sensor, such switches can be applied only to a limited extent in design appliances, since it is difficult to adapt the switch design to the design of the appliance.
The present invention is directed to resolving these and other matters.